In the past a number of machines have been proposed for cutting sod into small pieces for transplanting. Zoysia grass has become very popular, and machines for cutting this fine textured grass into small pieces or plugs for transplanting by consumers have been successful. However, such machines have not been successful for other types of grasses, particularly those of coarse texture.
For example, when dealing with Floritam or Bitter Blue varieties of St. Augustine grass, quite a problem is presented by the long "runners" that characterize these grasses, and the cutting of same has been a difficult problem for the Zoysia grass cutting machines to deal with.
Furthermore, whereas even a small plug of Zoysia grass can be expected to grow when transplanted to a suitable location, plugs of St. Augustine must necessarily be considerably larger, for otherwise they simply do not have a high success rate when transplanted. However, the problem of cutting St. Augustine grass into larger plugs by satisfactory means has not previously been solved.
The White, et al U.S. Pat. No. 2,889,878 entitled "Sod Cutting Machine with Gravity Feed Means" has a circular saw blade to cut sod to desired widths, and a shear cutter to cut the newly formed sod strips to a desired length. The Friedberg U.S. Pat. No. 4,043,231 entitled "Apparatus for Trimming and Scoring Cut Sod to Produce Separable Plugs" also uses a rotatable saw blade that serves to cut the sod sections into plugs, but both of these prior art devices require considerable amounts of hands-on efforts, and in addition are quite dangerous, despite safety measures taken to prevent a user from being cut by the blades. Furthermore, more than one pass of a section of sod through the Friedberg machine is necessary if the strips of sod cut as a result of the first pass through the blades are to be further acted upon to convert them into small pieces of sod suitable for transplanting. Therefore, it is to be seen that neither of these machines function automatically, yet entail considerable complexity.
The Dye U.S. Pat. No. 3,509,789 entitled "Sod-Cutting Apparatus" represents a machine that does not use rotating saw blades for cutting sod into small pieces or plugs for transplanting. However, inherent in the Dye design is a slow and tedious operation, in which sod sections are dealt with on a piece-by-piece basis, thus requiring a great deal of hand effort. Therefore, it is to be seen that Dye depends upon the operator for productivity. Dye uses a stationary stripper but this arrangement is not only a manually controlled arrangement, but also it is very dangerous to the operator. Furthermore, this patentee finds it necessary to use a stripper device for preventing the freshly cut plugs from clogging the cutting devices utilized.
The Nunes U.S. Pat. No. 3,807,505 entitled "Sod Handling Machine and Method" machine is a highly complex sod harvester machine, limited to use with elongate ribbons of sod that are to be cut into predetermined lengths. In fact, this may be regarded as a typical sod harvester. Thus, it is to be seen that none of the aforementioned prior art machines is designed for cutting St. Augustine grasses into plugs or circlets, nor do they address the special problems these grasses impose because of their coarse, loose texture.
The Dutch Pat. No. 6405345 of Nov. 17, 1964 is not a sod cutter at all, but apparently is a device for cutting floor tiles or the like, wherein the cutting stroke is short. This patentee utilized cutter array having free standing blades as shown in FIG. 4 of the patent, which blades would be subject to substantial bending, and clearly not able to cut coarse sod into circlets. Although the Dutch device would cut tiles or the like into a hexagonal shape, it utilizes blades strung out over comparatively long distances, hence unsatisfactory from the standpoint of defining a compact arrangement usable in a machine of reasonable size designed to operate in the field. Additionally, the arrangement taught in FIG. 5 of the Dutch patent would result in a considerable amount of wastage along both edges of the device.
It was in accordance with efforts to provide a machine for rapidly and automatically cutting large sections of coarse grass into properly sized pieces or plugs for ready packaging and subsequent transplanting that the present invention was evolved.